A new law introduced today has cleared the way for someone to be re-tried if new compelling evidence emerges.
President Mary McAleese has signed into law the Criminal Procedures Act 2010 which will allow the DPP to apply to have an acquittal quashed and a retrial ordered.
Minister for Justice and Law Reform Dermot Ahern said: "The signing into law of this Bill is a very major and historic development in our criminal law.
"This provides, for the first time, for retrials following acquittals if new and compelling evidence emerges, or where the first trial was tainted by an issue such as perjury or intimidation.
"There would also be provision for a retrial where the judge at the first trial erred in law by, for example, excluding certain evidence."
"This will be welcomed by most people, especially by the victims, who feel affronted and scandalised by the knowledge that guilty persons were not being convicted for their crimes."
The Minister stressed that retrials could happen only in serious cases and only after the courts had granted an application made by the DPP to quash the acquittal and order a retrial.
The Act sets high thresholds which the DPP will be required to meet before an application is made.
The Minister said that the new Act also provided vital benefits for victims of crime. He said it will benefit victims in two very significant ways.
The expanded provision on victim impact statements will bring immediate benefit to victims and their families who wish to make a victim impact statement.
Minister Ahern said he was especially pleased that this Act reforms the law in this area. He said "the range of offences where there is to be an entitlement to make a statement is being expanded beyond those causing physical injury, and will in future cover offences causing emotional distress, such as harassment and stalking.
"I am very pleased that the new and expended entitlements to make victim impact statements will also close a gap which left families of deceased victims, for example, in murder trials, without a full entitlement to make a statement. It will also be easier for children or other vulnerable persons to make a statement."
The Act includes several other issues that will improve court procedures and help them operate more effectively.
The Minister plans to bring the Act into operation as soon as possible.